Congenital Heart Disease

1356764 - Accuracy of Postnatal Non-sedated Non-contrast MRI in Prenatally Diagnosed Vascular Rings

Friday, January 27, 2023

12:20 PM – 1:20 PM

Location: Pacific Jewel

Presenting Author(s)

NM

Namrita Mozumdar, MD

Advanced Imaging Fellow
Nemours Children's Hospital, United States

Primary Author(s)

NM

Namrita Mozumdar, MD

Advanced Imaging Fellow
Nemours Children's Hospital, United States

Co-Author(s)

DM

Dennis Mullen, RT

Medical Imaging Post Processing Lead
Nemours Children's Hospital, United States
DS

David Saul, MD

Radiologist
Nemours Children's Hospital, United States
RL

Richard Lorber, MD

Attending Pediatric Cardiologist
Nemours Children's Hospital, United States
SS

Shubhika Srivastava, MD

Chief of Cardiology
Nemours Children's Hospital, United States
MC

Mark Cartoski, MD

Director of Cardiac MRI
Nemours Children's Hospital
Wilmington, Delaware, United States
SN

Shannon Nees, MD

Attending Pediatric Cardiologist
Nemours Children's Hospital, United States

Background: Vascular rings are rare congenital anomalies of aortic arch development that can be associated with respiratory symptoms and feeding difficulty due to encirclement of the trachea and esophagus. Prenatal detection of vascular rings has increased with advances in ultrasound screening and fetal echocardiography, allowing for earlier identification of patients at risk. Echocardiography and computed tomography are typically used for postnatal confirmation of the aortic arch anatomy in neonates and infants. Non-contrast, non-sedated magnetic resonance imaging (MRI) can be used to confirm the vascular anatomy and assess for evidence of airway narrowing, avoiding the need for radiation and iodinated contrast in this at-risk population.

Methods: A retrospective single center chart review of infants with a prenatal diagnosis of right aortic arch and a postnatal MRI was performed. MRI was performed non-sedated using a feed and swallow technique on a 1.5T scanner. Images obtained included bright and black blood sequences in axial, coronal, and sagittal planes as well as 3D whole-heart imaging. Results of fetal and post-natal echocardiograms, MRI, and surgical reports were reviewed. Diagnoses were compared to identify discrepancies.

Results: From 2020 to 2022, 14 infants with prenatal diagnosis of right aortic arch made at a mean gestational age of 26 weeks [21-32 weeks] underwent post-natal, non-sedated, non-contrast MRI at a mean age of four weeks [2-10 weeks]. All had adequate diagnostic images and were confirmed to have a vascular ring on MRI (Figure 1, 2). Mean study time was 42 mins [27-83 mins]. There were no patient complications. Fetal echocardiographic diagnosis was concordant with MRI diagnosis in 10 infants (71%) and discrepant in 4 infants (29%) (Figure 3). For 10 (71%) patients with fetal diagnosis of right aortic arch with aberrant left subclavian artery (RAA/ALSCA), MRI confirmed the fetal diagnosis. Two of those patients underwent surgery for symptoms and the diagnosis was confirmed at the time of surgery. In two patients with fetal diagnosis of RAA/ALSCA, MRI was consistent with a double aortic arch (DAA) and surgery confirmed DAA in both patients. One patient with fetal diagnosis of RAA with right patent ductus arteriosus was found to have RAA with aberrant left innominate on MRI. In the one patient with fetal diagnosis of DAA, MRI was consistent with RAA/ALSCA. Of those who underwent surgical repair, two (50%) had postnatal symptoms and three (75%) had evidence of airway compression on MRI.

Conclusion: Postnatal MRI, using feed and swaddle technique without use of radiation, contrast, or sedation, provides accurate postnatal diagnosis of vascular rings and airway narrowing prior to surgical repair. In the context of recent concerns regarding use of iodinated contrast in young children, the availability of MRI as a diagnostic tool has become more relevant. The non-sedated and non-contrast nature of this MRI technique further minimizes patient risk and parental anxiety.